The web of trust (mywot.com) service is a very good source, as well as a rare one for checking how reliable a website is. The wot service has some very good and reliable ratings, which can be used to keep your browsing more secure. However, it also has scam websites given very high ratings, which the wot users have no affect over. I just read a few comments on wot, so I thought why not review it on ciao, since those comments remind me of my experience with the wot service.
Until I got first hand experience of the problem of unreliable, wot owner oriented ratings, I didn't know wot to have a bad side to it. If it was to be a one off, I'd think someone had outsmarted wot's antispam system to give their scam website an extremely high rating. Lately however, many of the wot users that I know experiencing similar issues, have been rethinking the reliability of wot's ratings. This especially as wot doesn't usually count ratings given by its users, this is clear from pages where websites are given really bad comment ratings by hundreds of users, sometimes thousands, and the website is rated trustworthy by wot, and it has a wot trust seal.
Some users think this is due to an unknown error, a bug of some kind. I can neither say I accept that theory, nor completely reject it. I've been using the wot addon on my browsers for a number of years, and most of the time I found it of some use. Lately, I've began using trafficlight and kaspersky url advisor alongside it.
As most of my browsing is on my ubuntu PC, I don't have kaspersky url advisor on it, but I do have trafficlight. Trafficlight on many occasions, found websites to be malicious, while wot showed them to be highly trustworthy. Sometimes scam websites change their domain name or extension, so that they can start with a clean slate on wot. A great example of such scam websites is smarttweak. That's one of many examples, but others maybe able to give more off the top of their head. It took many complaints from wot users to get the high ratings on smarttweak changed to low, but then smarttweak changed their domain extension from .com to .org.
My advice would be to continue using wot, if you already use it. But don't use the rating charts as a definitive guideline to the trustworthiness of a website, remember to read users' comments and if possible install another secure browsing addon for your internet browser.
WOT started off very good, but over time scam websites have found various methods to either get extremely high ratings, or start from scratch when their ratings drop. I think wot is falling behind, and needs some serious updating.
One last thing to note, WOT sells trust seals here: http://www.mywot.com/en/trustseal/comparison
This is a page of wot, which show's a simple method for crooks to buy high ratings.
mywot.com - Web Of Trust 
